CN116729370A - Industrial vehicle - Google Patents

Abstract

An industrial vehicle suppresses deviation of a traveling direction of the industrial vehicle identified by a control device from an actual traveling direction of the industrial vehicle. The forklift includes a vehicle speed detection sensor, a steering lever, an object detection unit, and a control device. The steering rod determines the direction of travel. The object detection unit detects the position of an object existing in the direction of travel of the forklift. The control device is in a specific state when the speed of the forklift is equal to or greater than the 1 st vehicle speed threshold. The specific state is the following state: even if the travel direction command given by the steering wheel is changed, the control device recognizes that the state before the change is continued, and the object detection unit functions based on the state before the change.

Description

Industrial vehicle

Technical Field

The present disclosure relates to industrial vehicles.

Background

The industrial vehicle disclosed in patent document 1 includes a control device, a direction sensor, and a steering lever. The control device controls the industrial vehicle. The direction sensor detects the operation direction of a steering lever that determines the traveling direction. The direction sensor detects whether the direction lever is operated in a direction indicating forward movement or in a direction indicating backward movement with respect to the neutral position. The control device switches the traveling mode according to the operation of the steering lever. The travel modes include a forward mode and a reverse mode. When the steering lever is in the forward position, the control device sets the industrial vehicle to the forward mode. When the steering lever is in the retracted position, the control device sets the industrial vehicle to the retracted mode. When the speed of the industrial vehicle is equal to or higher than a predetermined speed, the control device maintains the travel mode even if the travel direction indicated by the steering lever is changed. In this case, the travel direction indicated by the steering lever is opposite to the travel direction of the industrial vehicle.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2006-322413

Disclosure of Invention

Problems to be solved by the invention

Industrial vehicles sometimes include an object detection unit. The object detection unit detects the position of an object existing in the traveling direction of the industrial vehicle. When the control device recognizes the traveling direction indicated by the steering lever as the traveling direction of the industrial vehicle, the traveling direction recognized by the control device is opposite to the actual traveling direction of the industrial vehicle from the time when the position of the steering lever is switched to the time when the traveling direction of the industrial vehicle is switched. In this case, the control device may not recognize an object existing in the actual traveling direction of the industrial vehicle.

Solution for solving the problem

An industrial vehicle for solving the above problems is provided with: a traveling direction detection unit that detects a traveling direction of an industrial vehicle; a vehicle speed detection sensor that detects a speed of the industrial vehicle; a travel direction determining unit that determines a travel direction of the industrial vehicle; an object detection unit that detects a position of an object existing in a traveling direction of the industrial vehicle; and a control device that, when the speed of the industrial vehicle detected by the vehicle speed detection sensor is equal to or greater than a 1 st vehicle speed threshold, sets a specific state that is a state in which: even if the traveling direction instruction given by the traveling direction determining section changes, the control device recognizes that the state before the change is continued, and the object detecting section functions based on the state before the change.

When the traveling direction command given by the traveling direction determining unit changes while the industrial vehicle is traveling, the traveling direction of the industrial vehicle is switched after the speed of the industrial vehicle decreases. When the travel direction command given by the travel direction determining unit is changed when the speed of the industrial vehicle is equal to or greater than the 1 st vehicle speed threshold, the travel direction of the industrial vehicle is maintained at least until the speed of the industrial vehicle becomes lower than the 1 st vehicle speed threshold. When the speed of the industrial vehicle is equal to or greater than the 1 st vehicle speed threshold, the control device is in a specific state. In the specific state, even if the traveling direction instruction given by the traveling direction determining section changes, the control device recognizes that the state before the change is continued. This can suppress a deviation between the traveling direction of the industrial vehicle identified by the control device and the actual traveling direction of the industrial vehicle. Even if the travel direction command given by the travel direction determining unit is changed, the object detecting unit functions based on the state before the change, and can detect the object in conformity with the travel direction of the industrial vehicle.

In the above-described industrial vehicle, the industrial vehicle may further include a notification unit configured to notify that the object detected by the object detection unit is likely to be in contact with the industrial vehicle, and the control device may determine whether the object is likely to be in contact with the industrial vehicle based on the state before the change in the specific state.

The industrial vehicle may further include: an engine; and a power transmission mechanism capable of switching a drive transmission state in which a drive force of the engine is transmitted to the power transmission mechanism and a drive non-transmission state in which the drive force of the engine is not transmitted to the power transmission mechanism, the control device setting the power transmission mechanism to the drive non-transmission state in the specific state.

In the industrial vehicle, the industrial vehicle may further include an interlock device that sets the power transmission mechanism in the drive non-transmission state, and the control device may set the power transmission mechanism in the drive non-transmission state by the interlock device when the travel direction command given by the travel direction determining unit changes when the speed of the industrial vehicle is equal to or greater than a 2 nd vehicle speed threshold that is greater than a 1 st vehicle speed threshold, and the 1 st vehicle speed threshold may be set to be lower than the 2 nd vehicle speed threshold.

Effects of the invention

According to the present invention, it is possible to suppress a deviation between the traveling direction of the industrial vehicle recognized by the control device and the actual traveling direction of the industrial vehicle.

Drawings

Fig. 1 is a perspective view of a forklift.

Fig. 2 is a schematic configuration diagram of the forklift.

Fig. 3 is a schematic configuration diagram of the traveling system.

Fig. 4 is a flowchart showing the object detection process.

Fig. 5 is a diagram schematically showing an expected trajectory.

Fig. 6 is a diagram schematically showing an expected trajectory.

Fig. 7 is a diagram schematically showing an expected trajectory.

Fig. 8 is a diagram schematically showing an expected trajectory.

Fig. 9 is a flowchart showing notification control.

Fig. 10 is a schematic diagram for explaining the function of the embodiment.

Fig. 11 is a schematic diagram for explaining the function of the embodiment.

Fig. 12 is a schematic configuration diagram of a forklift of a modification.

Description of the reference numerals

10 … as a forklift for industrial vehicles, 31 … engine, 40 … power transmission mechanism, 81 … control device, 89 … as a steering lever of a travel direction determining section, 90 … as a direction switch of a travel direction detecting section, 110 … interlock, 131 … object detecting section, 136 … notification section.

Detailed Description

An embodiment of the industrial vehicle will be described below.

< fork truck >

As shown in fig. 1, a forklift 10 as an industrial vehicle includes a vehicle body 11, 2 driving wheels 12, 2 steering wheels 14, and a cargo handling device 20. In the following description, the front, rear, left and right refer to the front, rear, left and right of the forklift 10.

The vehicle body 11 includes a roof 15 provided at an upper portion of a driver's seat. The 2 drive wheels 12 are arranged at the front of the vehicle body 11. The 2 drive wheels 12 are disposed apart from each other in the vehicle width direction. The 2 steering wheels 14 are disposed at the rear of the vehicle body 11. The 2 steering wheels 14 are arranged apart from each other in the vehicle width direction.

The cargo handling device 20 includes a mast 21, 2 forks 22, and a lift cylinder 23. The mast 21 is provided at the front of the vehicle body 11. The fork 22 is arranged to be liftable together with the mast 21. The fork 22 is loaded with cargo. The lifting cylinder 23 is a hydraulic cylinder. The mast 21 is lifted and lowered by the extension and contraction of the lift cylinder 23. The fork 22 is lifted and lowered along with the lifting and lowering of the mast 21. The forklift 10 of the present embodiment is a forklift that performs a traveling operation and a cargo handling operation by a rider's operation.

< Structure of fork truck >)

As shown in fig. 2, the forklift 10 includes: the travel system 30, the control device 81, the accelerator pedal 86, the acceleration sensor 87, the tire angle sensor 88, the steering lever 89, the direction switch 90, the forward link 101, the reverse link 102, the forward detection line 103, the reverse detection line 104, the interlock device (interlock) 110, and the object detection unit 131.

< running System >)

As shown in fig. 3, the travel system 30 is a mechanism for traveling the forklift 10. The travel system 30 includes: the engine 31, the output shaft 33, the rotation speed sensor 34, the power transmission mechanism 40, the solenoid valve 50, the forward solenoid 51, the reverse solenoid 52, the differential device 60, the axle 61, the vehicle speed detection sensor 62, and the travel control device 63.

The engine 31 is a driving source for the traveling operation and the cargo handling operation of the forklift 10. The engine 31 of the present embodiment is a gasoline engine that uses gasoline as fuel. The engine 31 is provided with a throttle actuator 32. The throttle actuator 32 adjusts the throttle opening of a throttle valve, not shown, provided in the intake path so as to follow the target rotational speed of the engine 31 calculated from the opening of the accelerator pedal 86. By adjusting the throttle opening by the throttle actuator 32, the amount of air to the engine 31 can be adjusted. Thereby, the rotation speed of the engine 31 is controlled. As the engine 31, a diesel engine using light oil as fuel may be used. As the engine 31, an engine using liquefied petroleum gas or compressed natural gas as a fuel may be used. The output shaft 33 is coupled to the engine 31. The output shaft 33 is rotated by the driving of the engine 31.

The rotation speed sensor 34 is provided on the output shaft 33. The rotation speed sensor 34 detects the rotation speed of the engine 31. The rotation speed of the engine 31 refers to the rotation speed of the output shaft 33. The rotation speed sensor 34 outputs an electric signal corresponding to the rotation speed of the output shaft 33 to the travel control device 63.

The power transmission mechanism 40 transmits the driving force of the engine 31 to the driving wheels 12. The power transmission mechanism 40 includes a torque converter 41 and a transmission 42.

The torque converter 41 is coupled to the output shaft 33. The driving force of the engine 31 is transmitted to the torque converter 41 via the output shaft 33. The torque converter 41 includes a pump coupled to the output shaft 33, and a turbine. In the torque converter 41, the turbine is rotated by the hydraulic oil discharged from the pump.

The transmission 42 includes an input shaft 43, a forward clutch 44, a forward gear train 45, a reverse clutch 46, a reverse gear train 47, and an output shaft 48. The input shaft 43 is coupled to the torque converter 41. The driving force is transmitted from the torque converter 41 to the transmission 42 via the input shaft 43.

The forward clutch 44 is provided to the input shaft 43. The forward gear train 45 is disposed between the forward clutch 44 and the output shaft 48. The forward clutch 44 is switched to the connected state or the disconnected state. The connected state is a state in which the input shaft 43 and the forward gear train 45 are connected. The cut-off state is a state in which the input shaft 43 and the forward gear train 45 are cut off. In the case where the input shaft 43 and the forward gear train 45 are connected through the forward clutch 44, the driving force is transmitted from the input shaft 43 to the forward gear train 45. The driving force transmitted to the forward gear train 45 is transmitted to the output shaft 48. It can be said that the driving force of the engine 31 is transmitted to the output shaft 48 with the forward clutch 44 connected to the forward gear train 45. In the case where the forward clutch 44 and the forward gear train 45 are disconnected, the driving force is not transmitted from the input shaft 43 to the forward gear train 45. As the forward clutch 44, a hydraulic clutch is used. As the hydraulic clutch, for example, a wet type multiple plate clutch can be cited.

The reverse clutch 46 is provided to the input shaft 43. A reverse gear train 47 is provided between the reverse clutch 46 and the output shaft 48. The reverse clutch 46 is switched to the connected state or the disconnected state. The connected state is a state in which the input shaft 43 and the reverse gear train 47 are connected. The off state is a state in which the input shaft 43 and the reverse gear train 47 are disconnected. When the input shaft 43 and the reverse gear train 47 are connected by the reverse clutch 46, the driving force is transmitted from the input shaft 43 to the reverse gear train 47. The driving force transmitted to the reverse gear train 47 is transmitted to the output shaft 48. It can be said that the driving force of the engine 31 is transmitted to the output shaft 48 with the reverse clutch 46 connected to the reverse gear train 47. In the case where the reverse clutch 46 and the reverse gear train 47 are disconnected, the driving force is not transmitted from the input shaft 43 to the reverse gear train 47. As the reverse clutch 46, a hydraulic clutch is used. As the hydraulic clutch, for example, a wet type multiple plate clutch can be cited.

The solenoid valve 50 controls the supply of the hydraulic oil to the forward clutch 44 and the reverse clutch 46 and the discharge of the hydraulic oil from the forward clutch 44 and the reverse clutch 46. The connection state and the disconnection state of the clutches 44, 46 are switched by the supply and discharge of the hydraulic oil by the solenoid valve 50.

The solenoids 51 and 52 switch the supply and discharge of the hydraulic oil to and from the clutches 44 and 46 by the solenoid valve 50. Working oil is supplied from the solenoid valve 50 to the forward clutch 44 with the forward solenoid 51 energized. When the hydraulic oil is supplied to the forward clutch 44, the forward clutch 44 is in a connected state. When the reverse solenoid 52 is energized, hydraulic oil is supplied from the solenoid valve 50 to the reverse clutch 46. When the working oil is supplied to the reverse clutch 46, the reverse clutch 46 is in a connected state.

As the solenoid valve 50, 1 electromagnetic direction switching valve may be used. The electromagnetic direction switching valve is a solenoid valve that switches a spool (spool) to a position where the hydraulic oil 4 is supplied to the forward clutch 44 when the forward solenoid 51 is energized, and switches a spool to a position where the hydraulic oil is supplied to the reverse clutch 46 when the reverse solenoid 52 is energized. When both the forward solenoid 51 and the reverse solenoid 52 are demagnetized, the spool of the electromagnetic direction switching valve is switched to a position where hydraulic oil is discharged from the two clutches 44, 46. The hydraulic fluid for operating the forward clutch 44 and the reverse clutch 46 is supplied from a hydraulic pump provided inside the power transmission mechanism 40. The structure of the hydraulic pump is known.

As the solenoid valve 50, 2 solenoid valves may be used. Each of the 2 solenoid valves is provided corresponding to the forward clutch 44 and the reverse clutch 46, respectively. In this case, the supply of the hydraulic oil to the two clutches 44 and 46 and the discharge of the hydraulic oil from the two clutches 44 and 46 may be performed by controlling the respective solenoid valves 50 individually by the forward solenoid 51 and the reverse solenoid 52.

The power transmission mechanism 40 can be switched between a drive transmission state in which the driving force of the engine 31 is transmitted to the power transmission mechanism 40, and a drive non-transmission state in which the driving force of the engine 31 is not transmitted to the power transmission mechanism 40. When either one of the forward clutch 44 and the reverse clutch 46 is in the connected state, the driving force of the engine 31 is transmitted to the power transmission mechanism 40, and the forklift 10 travels. The case where either one of the forward clutch 44 and the reverse clutch 46 is in the connected state is a drive transmission state. When the forward clutch 44 and the reverse clutch 46 are in the disengaged state, the driving force of the engine 31 is not transmitted to the power transmission mechanism 40. The forward clutch 44 and the reverse clutch 46 are in the off state, and are in the drive non-transmission state.

The differential 60 is coupled to the output shaft 48. The axle 61 is coupled to the differential 60. The axle 61 is coupled to the drive wheel 12. By the rotation of the output shaft 48, the axle 61 rotates. By the rotation of the axle 61, the drive wheel 12 rotates, and the forklift 10 thereby travels. If the forward clutch 44 is connected with the forward gear train 45, the truck 10 is advanced. If the reverse clutch 46 is connected with the reverse gear train 47, the truck 10 is reversed.

The vehicle speed detection sensor 62 is a sensor for detecting the vehicle speed of the forklift 10. The vehicle speed detection sensor 62 is provided, for example, on the output shaft 48 or the axle 61. The vehicle speed detection sensor 62 outputs a pulse signal corresponding to the vehicle speed of the forklift 10 to the travel control device 63.

The travel control device 63 is an engine control unit that performs control of the engine 31. The travel control device 63 adjusts the throttle opening by controlling the throttle actuator 32. By adjusting the throttle opening, the driving force of the engine 31 is adjusted.

Control device

As shown in fig. 2, the control device 81 includes a processor 82 and a storage unit 83. Examples of the processor 82 include a CPU (Central Processing Unit: central processing unit), a GPU (Graphics Processing Unit: graphics processing unit), and a DSP (Digital Signal Processor: digital signal processor). The storage unit 83 includes a RAM (Random Access Memory: random access Memory) and a ROM (Read Only Memory). The storage unit 83 stores program codes or instructions configured to cause the processor 82 to execute processing. The storage 83, i.e., the computer-readable medium, includes all available media that can be accessed by a general purpose or special purpose computer. The control device 81 may be constituted by a hardware circuit such as an ASIC (Application Specific Integrated Circuit: application specific integrated circuit) or an FPGA (Field Programmable Gate Array: field programmable gate array). The control device 81 as a processing circuit may include 1 or more processors operating in accordance with a computer program, 1 or more hardware circuits such as an ASIC or FPGA, or a combination thereof.

Acceleration sensor and tire angle sensor

The accelerator sensor 87 detects the operation amount of the accelerator pedal 86. The operation amount of the accelerator pedal 86 can also be said to be an accelerator opening. The acceleration sensor 87 outputs an electric signal corresponding to the accelerator opening degree to the control device 81. The control device 81 can recognize the accelerator opening degree by an electric signal from the acceleration sensor 87.

The tire angle sensor 88 detects the steering angle of the steering wheel 14. The tire angle sensor 88 outputs an electric signal corresponding to the steering angle to the control device 81. The control device 81 can recognize the steering angle by an electric signal from the tire angle sensor 88.

< steering column >

The steering lever 89 determines the direction of travel of the truck 10. The steering lever 89 is operated by the rider of the forklift 10. The steering lever 89 is operated to a forward position indicating forward movement or a reverse position indicating reverse movement with reference to the neutral position. For example, the forward position is a position where the steering lever 89 is tilted forward from the neutral position. The retracted position is a position in which the steering lever 89 is tilted rearward from the neutral position. The steering lever 89 is a travel direction determining unit. The rider can give a travel direction instruction to the forklift 10 by operating the steering lever 89. The travel direction command is a command indicating the travel direction of the forklift 10. The travel direction instruction includes a forward instruction and a backward instruction. The forward command is a command indicating the forward movement of the forklift 10. The backward instruction is an instruction to instruct the forklift 10 to backward.

< Direction switch >)

The direction switch 90 is switched according to the operation direction of the direction lever 89. The direction switch 90 includes 1 movable contact 91 and 3 fixed contacts 92, 93, 94. The movable contact 91 is connected to the positive electrode of the battery mounted on the forklift 10. The 3 fixed contacts 92, 93, 94 include a neutral fixed contact 92, a forward fixed contact 93, and a backward fixed contact 94. When the steering lever 89 is in the neutral position, the movable contact 91 is connected to the neutral fixed contact 92. When the steering lever 89 is in the forward position, the movable contact 91 is connected to the forward fixed contact 93. When the steering lever 89 is in the retracted position, the movable contact 91 is connected to the retracted fixed contact 94. The direction switch 90 is a travel direction detecting section. The direction switch 90 may be constituted by 3 buttons including a forward position, a neutral position, and a backward position, and contacts may be connected when the buttons are operated.

< advancing connection line and retreating connection line >)

The advancing wire 101 connects the advancing fixed contact 93 with the advancing solenoid 51. In the case where the movable contact 91 and the advance fixed contact 93 are connected, the advance connection line 101 and the battery are electrically connected. Thereby, the forward solenoid 51 is excited. When the movable contact 91 and the forward fixed contact 93 are connected, the backward solenoid 52 is demagnetized.

The retract link 102 connects the retract fixed contact 94 with the retract solenoid 52. When the movable contact 91 and the retracting fixed contact 94 are connected, the retracting connection 102 is electrically connected to the battery. Thereby, the reverse solenoid 52 is excited. When the movable contact 91 and the retracting fixed contact 94 are connected, the advancing solenoid 51 is demagnetized.

When the steering rod 89 is in the forward position, the forward solenoid 51 is energized to supply hydraulic oil to the forward clutch 44. Thereby, the forklift 10 can advance. When the steering lever 89 is in the retracted position, the retraction solenoid 52 is energized to supply hydraulic oil to the retraction clutch 46. Thereby, the forklift 10 can be retracted. When the steering lever 89 is in the neutral position, the two solenoids 51 and 52 are demagnetized, and the hydraulic oil is not supplied to the clutches 44 and 46. In this case, the driving force of the engine 31 is not transmitted to the power transmission mechanism 40.

< forward detection line and backward detection line >)

The advance detection line 103 connects the advance connection line 101 with the control device 81. In the case where a voltage from a battery is applied to the forward connection line 101, the voltage is applied to the control device 81 via the forward detection line 103. The back detection line 104 connects the back connection line 102 to the control device 81. When a voltage from the battery is applied to the reverse connection line 102, the voltage is applied to the control device 81 via the reverse detection line 104. When a voltage is input from the advance detection line 103, the control device 81 can determine that the steering lever 89 is in the advance position. When a voltage is input from the reverse detection line 104, the control device 81 can determine that the steering lever 89 is in the reverse position. Specifically, the control device 81 includes a port 84 connected to the forward detection line 103 and a port 85 connected to the backward detection line 104. If a voltage is applied to the port 84, the control device 81 can determine that the steering rod 89 is in the forward position. If a voltage is applied to the port 85, the control device 81 can determine that the steering rod 89 is in the retracted position. The control device 81 can determine that the steering lever 89 is in the neutral position when no voltage is input to both the forward detection line 103 and the backward detection line 104. If the steering rod 89 is advanced, the control device 81 determines that an advance command is input. If the steering lever 89 is in the retracted position, the control device 81 determines that the retraction command is input.

< interlocking device >)

The interlock device 110 includes a forward relay 111 and a reverse relay 112. The forward relay 111 is provided to the forward connecting line 101. The forward relay 111 is switched to the connected state or the disconnected state. When the forward relay 111 is in the connected state, the forward connecting wire 101 and the forward solenoid 51 are electrically connected. When the forward relay 111 is in the off state, the forward connecting wire 101 and the forward solenoid 51 are electrically disconnected. The back relay 112 is provided to the back connection line 102. The backup relay 112 is switched to the connected state or the disconnected state. When the reverse relay 112 is in the connected state, the reverse connection line 102 and the reverse solenoid 52 are electrically connected. When the reverse relay 112 is in the off state, the reverse connection line 102 and the reverse solenoid 52 are electrically disconnected.

< object detection portion >)

The object detection unit 131 includes a stereo camera 132, a detection device 133, and a notification unit 136. The stereo camera 132 includes 2 cameras, and captures images with the 2 cameras. As shown in fig. 1, the stereo camera 132 is disposed on the ceiling 15. The stereo camera 132 is disposed so as to be capable of overlooking a road surface on which the forklift 10 travels from above the forklift 10. The stereo camera 132 of the present embodiment photographs the rear of the forklift 10. Thus, the object detected by the object detecting unit 131 becomes an object behind the forklift 10. The detection direction of the object detection portion 131 can be said to be the rear. The notification unit 136 and the detection device 133 may be unitized with the stereo camera 132 and disposed on the ceiling 15 together with the stereo camera 132. The notification unit 136 and the detection device 133 may be disposed at a position different from the ceiling 15.

The detector 133 includes a processor 134 and a storage unit 135. As the processor 134, for example, a CPU, GPU, or DSP is used. The storage section 135 includes RAM and ROM. The storage section 135 stores various programs for detecting an object from an image captured by the stereo camera 132. The storage unit 135 can be said to store program codes or instructions configured to cause the processor 134 to execute processing. Storage 135, i.e., a computer-readable medium, includes all available media that can be accessed by a general purpose or special purpose computer. The detection device 133 may be constituted by a hardware circuit such as an ASIC or FPGA. The detection device 133 as a processing circuit may include 1 or more processors operating in accordance with a computer program, 1 or more hardware circuits such as an ASIC or FPGA, or a combination thereof.

< object detection Process >)

The detection device 133 repeatedly performs the following object detection processing at predetermined control cycles, thereby detecting an object existing behind the forklift 10. In addition, the detection device 133 derives the position of the detected object. The position of the object refers to the relative position of the forklift 10 and the object.

As shown in fig. 4, in step S100, the detection device 133 acquires an image from the stereo camera 132.

Next, in step S110, the detection device 133 acquires a parallax image by performing stereoscopic processing. The parallax image is an image in which a parallax [ px ] is associated with a pixel. The parallax image is not necessarily an image to be displayed, but data indicating that each pixel in the parallax image corresponds to parallax. The parallax can be obtained by comparing 2 images captured by the stereo camera 132 and deriving the difference in the number of pixels between the images for the same feature point presented to each image. The feature point is a portion of the object that can be identified as a boundary, such as an edge. The feature points can be detected from luminance information or the like.

Next, in step S120, the detection device 133 derives coordinates of feature points within the world coordinate system, which is a coordinate system in real space. The world coordinate system is a coordinate system in which, in a state in which the forklift 10 is positioned on the horizontal plane, an axis extending in the vehicle width direction of the forklift 10 in the horizontal direction is an X axis, an axis orthogonal to the X axis in the horizontal direction is a Y axis, and an axis extending in the vertical direction is a Z axis. The derivation of the coordinates of the feature points is performed as follows: coordinates of the feature points in the camera coordinate system are derived from the base line length of the stereo camera 132, the focal length of the stereo camera 132, and the parallax image obtained in step S110, and then are converted into coordinates within the world coordinate system. As shown in fig. 1, an X-axis direction, a Y-axis direction, and a Z-axis direction are illustrated by arrows X, Y, Z.

As shown in fig. 4, in step S130, the detection device 133 performs extraction of an object by clustering (cluster) feature points. The detection device 133 extracts, as 1 point group, a set of feature points assumed to represent the same object among feature points which are points representing a part of the object, and extracts the point group as an object. The detection device 133 performs clustering in which feature points located within a predetermined range are regarded as 1 point group based on the coordinates of the feature points in the world coordinate system derived in step S120. The detection means 133 regards the clustered point group as 1 object. Further, the clustering of the feature points performed in step S130 can be performed by various methods.

Next, in step S140, the detecting device 133 derives coordinates of the object in the world coordinate system. The coordinates of the object can be derived from the coordinates of the feature points constituting the point group. The coordinates of the objects in the world coordinate system represent the relative positions of the truck 10 and the objects. Specifically, the X-coordinate among the coordinates of the object in the world coordinate system represents the distance from the origin to the left-right direction of the object, and the Y-coordinate represents the distance from the origin to the front-rear direction of the object. The origin is, for example, the position where the stereo camera 132 is arranged, the X-coordinate and the Y-coordinate, and the Z-coordinate, respectively, the road surface coordinate. The euclidean distance from the arrangement position of the stereo camera 132 to the object can also be derived from the X-coordinate and the Y-coordinate. The Z-coordinate among the coordinates of the object in the world coordinate system represents the height of the object from the road surface.

Next, in step S150, the detection device 133 performs a human detection process. The person detection process is a process of determining whether or not an object is a person. In the present embodiment, the detection device 133 performs a person detection process for an image captured by any one of the 2 cameras of the stereo camera 132. The detecting device 133 converts the coordinates of the object in the world coordinate system obtained in step S140 into camera coordinates, and converts the camera coordinates into coordinates of the image captured by the camera. The detection device 133 performs a human detection process for coordinates of an object in the image. The human detection processing is performed using, for example, the feature quantity. The detecting device 133 extracts feature amounts of coordinates of an object in the image. As the feature extraction, for example, extracted HOG: histogram of Oriented Gradients (directional gradient histogram) feature quantity, haar-Like feature quantity, and the Like. The detecting device 133 determines whether the object is a person by comparing the feature amount extracted from the image with the dictionary data. The dictionary data is, for example, data of feature amounts extracted from each of a plurality of known image data on which a person is present. In the following description, an object different from a person is sometimes referred to as an obstacle.

< report part >)

The notification unit 136 is a device that notifies the rider of the forklift 10. Examples of the notification unit 136 include a buzzer that notifies by sound, a lamp that notifies by light, or a combination thereof.

Control by control device

The control device 81, the travel control device 63, and the object detection unit 131 are configured to be able to acquire information from each other. The control device 81, the travel control device 63, and the object detection unit 131 acquire information from each other by performing communication in accordance with a vehicle communication protocol such as CAN (Controller Area Network: controller area network) or LIN (Local Interconnect Network: local interconnect network).

The control device 81 derives the vehicle speed of the forklift 10. The vehicle speed of the forklift 10 can be derived by using the detection result of the vehicle speed detection sensor 62, the gear ratio, the outer diameter of the driving wheel 12, the steering angle detected by the tire angle sensor 88, and the like. The detection result of the vehicle speed detection sensor 62 can be obtained from the travel control device 63. The gear ratio and the outer diameter of the drive wheel 12 may be stored in the storage unit 83 in advance. In the following description, the vehicle speed represents the vehicle speed of the forklift 10.

The control device 81 switches between the connected state and the disconnected state of the forward relay 111 and the reverse relay 112. When the switching back operation is not performed, the control device 81 sets the forward relay 111 and the reverse relay 112 to the connected state. When the vehicle speed is equal to or greater than the 2 nd vehicle speed threshold, the control device 81 turns off the forward relay 111 and the reverse relay 112. When the vehicle speed is lower than the 2 nd vehicle speed threshold, the control device 81 sets the forward relay 111 and the reverse relay 112 to the connected state. The turning action refers to an action in which the travel direction instruction given by the steering lever 89 is changed. The change in the travel direction instruction includes a change from a forward instruction to a reverse instruction and a change from a reverse instruction to a forward instruction. When the forward relay 111 and the reverse relay 112 are in the off state, the driving force of the engine 31 is not transmitted to the power transmission mechanism 40 because the solenoids 51, 52 are demagnetized, regardless of the position of the steering rod 89. That is, the power transmission mechanism 40 is in a drive non-transmission state. This reduces the load on the power transmission mechanism 40 when the vehicle speed is equal to or greater than the 2 nd vehicle speed threshold value and the reverse rotation operation is performed. The load on the power transmission mechanism 40 can be reduced as the 2 nd vehicle speed threshold is lowered. On the other hand, the time required for switching the traveling direction of the forklift 10 during the reverse operation increases as the 2 nd vehicle speed threshold is lowered. Based on these factors, the 2 nd vehicle speed threshold can be arbitrarily set.

The control device 81 transmits a notification instruction to the object detection unit 131 to operate the notification unit 136. Specifically, the object detection unit 131 includes an operation unit that operates the notification unit 136, and when receiving the notification instruction, the operation unit operates the notification unit 136.

< report area >

The control device 81 performs notification control. The notification control is control performed during traveling of the forklift 10, and is control in which notification by the notification unit 136 is performed in accordance with the detection condition of the object by the object detection unit 131. First, a notification area for notification control will be described.

As shown in fig. 5, a notification area AA1 for notification control is set in a detectable range of the object by the object detection unit 131. The detectable range of the object detection unit 131 for the object can be also referred to as a photographable range of the stereo camera 132. In the present embodiment, the notification area AA1 is the same area as the detectable range of the object by the object detection unit 131. The notification area AA1 is an area extending from the arrangement position of the stereo camera 132 toward the rear of the forklift 10 and the vehicle width direction of the forklift 10. The report area AA1 is an area defined by X coordinates and Y coordinates in the world coordinate system.

< predicted track >)

The control device 81 derives the expected trajectory T of the truck 10. The estimated trajectory T refers to a trajectory through which the forklift 10 is estimated to pass. In the present embodiment, the control device 81 derives the estimated trajectory T through which the forklift 10 is estimated to pass when the direction of travel of the forklift 10 is the backward direction.

The estimated trajectory T can be derived from the steering angle of the steering wheel 14 and the dimensional information of the forklift 10. The dimension information of the forklift 10 includes a dimension [ mm ], a wheelbase [ mm ] and a vehicle width [ mm ] from the center axis of the driving wheel 12 to the rear end of the vehicle body 11. Since the size information of the forklift 10 is known information, it can be stored in advance in the storage 83 of the control device 81. The estimated trajectory T is a trajectory between the trajectory LT through which the left end LE of the vehicle body 11 passes and the trajectory RT through which the right end RE of the vehicle body 11 passes. The control device 81 derives the X and Y coordinates of the expected trajectory T extending rearward of the truck 10 in the world coordinate system.

As shown in fig. 5 and 6, when the forklift 10 is traveling straight, the trajectory T is expected to be a trajectory extending linearly from the forklift 10 in the backward direction. As shown in fig. 7 and 8, when the forklift 10 is turning, the locus T is expected to be a locus curved in the backward direction from the forklift 10. When the forklift 10 is turning rightward, the trajectory T is expected to extend rightward. In the case where the forklift 10 is turning in the left direction, the locus T is expected to extend in the left direction. The control device 81 can be said to derive the estimated trajectory T extending in the turning direction when the forklift 10 is turning.

The forklift 10 shown in fig. 6 has a higher vehicle speed than the forklift 10 in the state shown in fig. 5. Similarly, the forklift 10 shown in fig. 8 has a higher vehicle speed than the forklift 10 shown in fig. 7. As shown in fig. 5 to 8, the control device 81 increases the estimated trajectory T in the traveling direction as the vehicle speed of the forklift 10 increases. In the present embodiment, the track-derived threshold YT is changed according to the vehicle speed. The trajectory derivation threshold YT is a threshold set for the Y coordinate in the world coordinate system, and becomes the Y coordinate farther from the forklift 10 as the vehicle speed increases. The control means 81 derives an expected trajectory T from the truck 10 to the trajectory derivation threshold YT. Further, extending the estimated trajectory T in the traveling direction as the vehicle speed of the forklift 10 increases is not limited to a method in which the vehicle speed of the forklift 10 and the length of the estimated trajectory T in the traveling direction are in a proportional relationship, and may have the following correlation: if the vehicle speed of the forklift 10 becomes high, the length of the trajectory T in the traveling direction is expected to become long. The predicted trajectory T is derived in the reporting area AA 1.

< report control >)

The notification control will be described. The notification control is repeated in a predetermined control cycle.

As shown in fig. 9, in step S1, the control device 81 determines whether or not a specific condition is satisfied. The specific condition is that the state in which the vehicle speed is lower than the 1 st vehicle speed threshold value continues for a prescribed time. The vehicle speed is an absolute value of the speed calculated using the detection result of the vehicle speed detection sensor 62. The 1 st vehicle speed threshold value can be set to an arbitrary value. In the present embodiment, the 1 st vehicle speed threshold value is a value lower than the 2 nd vehicle speed threshold value. The predetermined time is longer than the control period. The predetermined time is set so that, when the vehicle speed is instantaneously determined to be lower than the 1 st vehicle speed threshold value although the vehicle speed is equal to or higher than the 1 st vehicle speed threshold value due to the influence of noise, it is not determined that the specific condition is satisfied. If the determination result in step S1 is affirmative, the control device 81 performs the processing in step S2. If the determination result in step S1 is negative, the control device 81 performs the processing in step S3. When the specific condition is not satisfied, the vehicle speed is equal to or greater than a1 st vehicle speed threshold. If the vehicle speed is equal to or greater than the 1 st vehicle speed threshold, the process of step S3 may be performed.

In step S2, the control device 81 is in a normal state. The normal state is a state in which the traveling direction of the forklift 10 is determined based on the detection result of the direction switch 90. If the steering lever 89 is advanced, the control device 81 determines that the traveling direction of the forklift 10 is the advancing direction. If the steering lever 89 is in the retracted position, the control device 81 determines that the traveling direction of the forklift 10 is the retraction direction. When the process of step S2 is completed, the control device 81 performs the process of step S4.

In step S3, the control device 81 is in a specific state. The specific state is a state in which even if the traveling direction instruction given by the steering lever 89 changes, the state before the change is recognized as being continued. If the travel direction command in the previous control cycle is a forward command, the control device 81 determines that the forward command is continued even if a reverse command is input from the direction switch 90. If the travel direction command in the previous control cycle is a reverse command, the control device 81 determines that the reverse command is continued even if a forward command is input from the direction switch 90. That is, even if the steering lever 89 is operated while the specific state is continued, the traveling direction command does not change. In the specific state, the vehicle speed is equal to or higher than the 1 st vehicle speed threshold. The 2 nd vehicle speed threshold value is a value larger than the 1 st vehicle speed threshold value. Therefore, it can be said that the control device 81 sets the power transmission mechanism 40 to the drive non-transmission state when the vehicle speed is equal to or higher than the 2 nd vehicle speed threshold value in the specific state. When the process of step S3 is completed, the control device 81 performs the process of step S4.

In step S4, the control device 81 determines whether or not the notification condition is satisfied. The notification condition refers to whether or not notification is performed by the notification unit 136. The notification condition is established when there is a possibility that the forklift 10 is in contact with an object. The notification condition differs depending on whether the object is a person or an obstacle. When the determination result in step S4 is affirmative, that is, when the notification condition is satisfied, the control device 81 performs the processing in step S5. In step S5, the control device 81 notifies the notification unit 136. Hereinafter, notification conditions will be described. The traveling direction for determining the notification condition differs depending on whether the control device 81 is in the normal state or the specific state. If the control device 81 is in the normal state, the traveling direction of the forklift 10 is determined based on the detection result of the direction switch 90. If the control device 81 is in a specific state, the travel direction of the forklift 10 is determined based on the travel direction command in the previous control cycle. It can be said that the control device 81 determines whether or not the object is likely to contact the forklift 10 based on the state before the change of the travel direction command is made in the specific state.

< case where the object is a person >

The notification condition in the case where the object is a person is that the forklift 10 is in the backward direction and a person is present in the notification area AA 1. When the forklift 10 is in the backward position and a person is present in the notification area AA1 in the case where the object detected by the object detection unit 131 is a person, the notification unit 136 notifies the person. In this case, if a person is present in the predicted trajectory T, the notification may be made stronger than if a person is present outside the predicted trajectory T. The report may be strengthened by: if the notification unit 136 is a buzzer, the buzzer sound is increased. If the notification unit 136 is a combination of a lamp and a buzzer, the notification is switched from using one of the lamp and the buzzer to using both of them. This makes it easy for the rider to recognize that an object is present in the predicted trajectory T.

< case where object is obstacle >)

The notification condition in the case where the object is an obstacle is that the forklift 10 is in the backward direction and there is an obstacle in the predicted trajectory T. When the object detected by the object detecting unit 131 is an obstacle, the notifying unit 136 notifies that the forklift 10 is in the backward direction and that an obstacle is present in the estimated trajectory T.

[ effects of the embodiment ]

As shown in fig. 10, it is assumed that the object O1 is present behind the forklift 10 in a state where the forklift 10 is in the backward direction. Arrow D1 indicates the actual direction of travel of the truck 10. Arrow D2 indicates the travel direction identified by the control device 81. When the rider of the forklift 10 performs a turning operation, the reverse command given by the steering lever 89 is switched to the forward command. When the traveling direction of the forklift 10 is switched, the speed of the forklift 10 is continuously decreased. For example, when the travel direction of the forklift 10 is switched from the backward direction to the forward direction, the speed of the forklift 10 is continuously decreased after the steering lever 89 is changed to the forward position. The traveling direction of the forklift 10 is switched to the forward direction by limiting the speed of the forklift 10 to 0 km/h. When the travel direction command given by the steering lever 89 is changed when the speed of the forklift 10 is equal to or higher than the 1 st vehicle speed threshold, it can be said that the travel direction of the forklift 10 is maintained at least until the speed of the forklift 10 becomes lower than the 1 st vehicle speed threshold.

If the speed of the forklift 10 is not the same, the control device 81 is maintained in a normal state. In this case, when the steering lever 89 is changed to the forward position, the control device 81 recognizes the actual traveling direction of the forklift 10 as the forward direction. In this case, even when the forklift 10 is actually still moving backward, the notification by the notification unit 136 is stopped at the time of changing the steering lever 89 to the forward position. That is, even if the distance L1 between the forklift 10 and the object O1 becomes shorter, the notification by the notification unit 136 is stopped at the time of changing the steering lever 89 to the advanced position.

In contrast, in the present embodiment, when the speed of the forklift 10 is equal to or greater than the 1 st vehicle speed threshold, the control device 81 is in a specific state. In the specific state, even if the traveling direction instruction given by the steering lever 89 changes, the control device 81 recognizes that the state before the change is continued. In the example shown in fig. 11, even if the reverse command is changed to the forward command by performing the reverse operation of the forklift 10, the control device 81 recognizes that the reverse command is continued. As a result, the control device 81 can recognize the traveling direction of the forklift 10 as the backward direction until the speed of the forklift 10 becomes lower than the 1 st vehicle speed threshold. Even if the travel direction command given by the steering lever 89 changes, the object detection unit 131 functions based on the state before the change, and thus can detect an object in accordance with the travel direction of the forklift 10. The object detection unit 131 functions to detect an object in the traveling direction of the forklift 10 by the object detection unit 131. Accordingly, even while the forklift 10 continues to travel due to inertia, the notification by the notification unit 136 is continued until the speed of the forklift 10 becomes lower than the 1 st vehicle speed threshold. If the conditions such as the speed of the forklift 10 when the turning operation is performed are the same, the distance L1 between the forklift 10 and the object O1 when the notification by the notification unit 136 is stopped can be made shorter than in the case shown in fig. 10.

Effect of the embodiment

(1) The control device 81 is in a specific state when the vehicle speed is equal to or greater than the 1 st vehicle speed threshold. Even if the travel direction command given by the steering lever 89 changes until the speed of the forklift 10 becomes lower than the 1 st vehicle speed threshold, the control device 81 can recognize that the travel direction of the forklift 10 is maintained. In comparison with a case where the traveling direction of the forklift 10 is recognized according to the operation position of the steering lever 89 regardless of the speed of the forklift 10, the deviation of the traveling direction of the forklift 10 recognized by the control device 81 from the actual traveling direction of the forklift 10 can be suppressed. Further, by causing the object detection unit 131 to function based on the thus identified traveling direction, an object can be detected in agreement with the traveling direction of the forklift 10.

(2) When the travel direction command of the steering lever 89 is changed in the specific state, the control device 81 determines whether or not there is a possibility of contact between the object and the forklift 10 based on the travel direction before the change of the travel direction command. This can suppress the notification by the notification unit 136 from stopping even when the forklift 10 approaches the object when the turning operation is performed.

(3) The control device 81 sets the power transmission mechanism 40 to the drive non-transmission state in the specific state. In the embodiment, the control device 81 sets the power transmission mechanism 40 to the drive non-transmission state when the control device 81 is in the specific state at a speed equal to or higher than the 2 nd vehicle speed threshold in the speed range. When the power transmission mechanism 40 is in the drive non-transmission state, the time required for switching the traveling direction of the forklift 10 becomes long when the reverse operation is performed. For example, if the traveling direction of the forklift 10 is the backward direction, the steering lever 89 is operated to switch the backward command to the forward command. At this time, when the power transmission mechanism 40 is in the drive non-transmission state, the distance traveled by the forklift 10 in the backward direction increases due to inertia. In other words, the distance required for switching the travel direction of the forklift 10 from the backward direction to the forward direction increases. As a result, when the control device 81 is maintained in the normal state regardless of the speed of the forklift 10, the distance in which the direction of travel of the forklift 10 recognized by the control device 81 deviates from the actual direction of travel of the forklift 10 becomes longer. When the notification is performed by the notification unit 136 if there is a possibility that the object is in contact with the forklift 10, the distance by which the notification by the notification unit 136 is not performed becomes longer although the forklift 10 approaches the object. In contrast, by bringing the control device 81 into the specific state, the distance in which the travel direction of the forklift 10 recognized by the control device 81 deviates from the actual travel direction of the forklift 10 can be shortened. When the notification is performed by the notification unit 136 in the case where there is a possibility that the object is in contact with the forklift 10, the distance that the notification by the notification unit 136 is not performed even though the forklift 10 is close to the object can be shortened.

(4) The control device 81 sets the power transmission mechanism 40 to the drive non-transmission state by the interlock device 110. The interlock device 110 is provided to reduce the load on the power transmission mechanism 40 when the reverse operation is performed when the vehicle speed is equal to or greater than the 2 nd vehicle speed threshold. On the other hand, by providing the interlock device 110, when the turning operation is performed when the vehicle speed is equal to or greater than the 2 nd vehicle speed threshold, the time required for switching the traveling direction of the forklift 10 becomes long. By making the 1 st vehicle speed threshold value smaller than the 2 nd vehicle speed threshold value, the control device 81 can recognize that the traveling direction of the forklift 10 is maintained from the time of the turning operation until the vehicle speed becomes lower than the 1 st vehicle speed threshold value when the turning operation is performed when the vehicle speed is equal to or higher than the 2 nd vehicle speed threshold value. Accordingly, when the turning operation is performed, the deviation between the travel direction of the forklift 10 recognized by the control device 81 and the actual travel direction of the forklift 10 can be suppressed.

(5) The specific condition is that the state in which the vehicle speed is lower than the 1 st vehicle speed threshold value continues for a prescribed time. Due to the influence of noise, the vehicle speed may be instantaneously determined to be lower than the 1 st vehicle speed threshold value, although the vehicle speed is equal to or higher than the 1 st vehicle speed threshold value. By setting the continuation of the predetermined time as a specific condition, erroneous determination due to the influence of noise can be suppressed.

Modification example

The embodiment can be modified as follows. The embodiments and the following modifications can be combined and implemented within a range that is not technically contradictory.

As shown in fig. 12, the running system 30 may include a brake mechanism 200. The brake mechanism 200 includes a brake actuator 201, a brake cylinder 202, and a brake controller 203.

The brake actuator 201 is an actuator that controls the hydraulic oil supplied to the brake cylinders 202. The brake actuator 201 controls the supply of the hydraulic oil, for example, by a solenoid valve.

The brake cylinder 202 is provided to the drive wheel 12. The brake cylinder 202 may be provided to the steering wheel 14. The wheel cylinders 202 generate friction braking forces by pressing brake pads against brake discs with hydraulic oil supplied from the brake actuators 201.

The hardware configuration of the brake controller 203 is the same as that of the control device 81, for example. The brake controller 203 controls the brake actuator 201 in response to a command from the control device 81. It can be said that the control device 81 can control the brake mechanism 200 by sending a command to the brake controller 203.

The control device 81 may control the brake mechanism 200 to apply a braking force to the forklift 10 in place of setting the power transmission mechanism 40 to the drive non-transmission state in the specific state. The control device 81 may control the brake mechanism 200 to apply a braking force to the forklift 10 in addition to the power transmission mechanism 40 being in the drive non-transmission state in the specific state.

The o control device 81 may not set the power transmission mechanism 40 to the drive non-transmission state in the specific state. In this case, the forklift 10 may not include the interlock 110.

The notification condition may not be changed depending on whether the object is a person or an obstacle. In this case, the detection device 133 may not perform the human detection process. The notification condition may be that the truck 10 is in a reverse position and that there is an object within the expected trajectory T. The notification condition may be that the forklift 10 is in the backward direction and an object is present in the notification area AA 1. In the case where the predicted trajectory T is not used as the notification condition, the control device 81 may not derive the predicted trajectory T.

The o control device 81 may perform deceleration control of the forklift 10 by recognizing the traveling direction of the forklift 10. For example, if the notification condition is satisfied, deceleration control for decelerating the forklift 10 may be performed. In this case, the notification by the notification unit 136 may be performed, or the notification by the notification unit 136 may not be performed.

The o control device 81 may set the power transmission mechanism 40 to the drive non-transmission state by an inching valve (inching valve). The inching valve adjusts whether the driving force of the engine 31 is distributed to the power transmission mechanism 40 or to the hydraulic pump. The power transmission mechanism 40 may be set to a drive non-transmission state by not distributing the driving force of the engine 31 to the power transmission mechanism 40 by the inching valve.

The specific condition may be that the vehicle speed is lower than the 1 st vehicle speed threshold.

The power transmission mechanism 40 may be configured to switch between the drive transmission state and the drive non-transmission state in response to a command from the control device 81. In this case, the control device 81 may give an instruction to the power transmission mechanism 40 at the time of the reverse operation, and may set the power transmission mechanism 40 in the drive non-transmission state.

The object detection unit 131 may detect the position of an object in the forward direction of the forklift 10. In this case, the stereo camera 132 is disposed toward the front of the forklift 10. When the object detection unit 131 detects the position of the object existing in the forward direction of the forklift 10, the notification area AA1 is an area extending forward from the forklift 10. In this case, in the notification control, control is performed such that "rear" and "front" described in the embodiment are reversed.

The object detection unit 131 may be an object detection unit that can detect the position of an object in either one of the backward direction and the forward direction among the traveling directions of the forklift 10. For example, a forward stereoscopic camera and a backward stereoscopic camera may be provided, or a fisheye camera may be provided. In this case, the notification area AA1 includes a front area extending forward from the forklift 10 and a rear area extending rearward from the forklift 10. The control device 81 changes the notification condition according to the traveling direction of the forklift 10. For example, if the traveling direction of the forklift 10 is the backward direction, the control device 81 notifies the notification unit 136 by the notification condition similar to the embodiment. If the traveling direction of the forklift 10 is the forward direction, the control device 81 replaces the backward direction in the notification conditions of the embodiment with the forward-backward direction, thereby notifying the notification unit 136.

The o direction determination unit may be any unit as long as it can be operated by the rider of the forklift 10. For example, the travel direction determining unit may be a button.

Instead of the stereo camera 132, the object detection unit 131 may use a monocular camera, a ToF (Time of Flight) camera, a LIDAR (Laser Imaging Detection and Ranging: laser imaging detection and ranging), a millimeter wave radar, or the like. The object detection unit 131 may include a plurality of sensors such as a stereo camera 132 and a LIDAR.

The part other than the object detection part 131 may be provided with a notification part 136.

The controller 81 may directly operate the notification unit 136.

The forklift 10 may be a forklift capable of switching between automatic operation and manual operation.

The o forklift 10 may be an electric forklift that runs by a motor.

The forklift 10 may be a forklift in which both a vehicle speed command and a travel direction determination are performed by a steering lever. Such a forklift is for example a reach forklift.

The rotation speed sensor 34 may be a travel direction detecting unit.

The detecting device 133 may be used as the control device.

The industrial vehicle may be a tractor for handling cargoes or the like, a picker for picking work, or the like.

Claims (4)

1. An industrial vehicle, comprising:

a traveling direction detection unit that detects a traveling direction of an industrial vehicle;

a vehicle speed detection sensor that detects a speed of the industrial vehicle;

a travel direction determining unit that determines a travel direction of the industrial vehicle;

an object detection unit that detects a position of an object existing in a traveling direction of the industrial vehicle; and

the control device is used for controlling the control device,

the control device is in a specific state when the speed of the industrial vehicle detected by the vehicle speed detection sensor is equal to or greater than a 1 st vehicle speed threshold value,

the specific state is the following state: even if the traveling direction instruction given by the traveling direction determining section changes, the control device recognizes that the state before the change is continued, and the object detecting section functions based on the state before the change.

2. The industrial vehicle as claimed in claim 1 wherein,

the industrial vehicle includes a notification unit that notifies that the object detected by the object detection unit is likely to come into contact with the industrial vehicle,

the control device determines whether or not the object is likely to be in contact with the industrial vehicle based on the state before the change in the specific state.

3. The industrial vehicle as claimed in claim 1 or claim 2 wherein,

the industrial vehicle includes:

an engine; and

the power transmission mechanism is provided with a power transmission mechanism,

the power transmission mechanism is capable of switching between a drive transmission state in which the driving force of the engine is transmitted to the power transmission mechanism and a drive non-transmission state in which the driving force of the engine is not transmitted to the power transmission mechanism,

the control device sets the power transmission mechanism to the drive non-transmission state in the specific state.

4. The industrial vehicle as claimed in claim 3, wherein,

the industrial vehicle includes an interlock device that sets the power transmission mechanism to the drive non-transmission state,

when the traveling direction instruction given by the traveling direction determining section is changed in the case where the speed of the industrial vehicle is equal to or greater than the 2 nd vehicle speed threshold value, the control means sets the power transmitting mechanism to the drive non-transmitting state by the interlocking means,

the 1 st vehicle speed threshold value is set lower than the 2 nd vehicle speed threshold value.